Amaryllidaceae alkaloids are secondary metabolites with interesting medicinal properties. Almost every
species can synthesize them and constitute an excellent source for their isolation and study. ...Several Amaryllidaceae alkaloids have shown acetylcholinesterase inhibitory activities and are a promising tool for treating cholinergic disorders such as Alzheimer's disease (AD). Indeed, three of the four palliative treatments approved for AD are acetylcholinesterase (AChE) inhibitors and one of them, galanthamine, is an Amaryllidaceae alkaloid itself. This molecule is currently isolated from natural sources. However, its production is insufficient to supply the increasing demand for the active principle. Our main aim is to discover tools to improve galanthamine production and to prospect for potential new and more efficient drugs for AD treatment. Furthermore, we seek to broaden the knowledge of plants of the genus
from a chemotaxonomic perspective. Hence, in this study, we evaluate the alkaloid content through GC-MS and the AChE inhibitory activity of ten autumn-flowering
, which have been less studied than their spring-flowering counterparts. A total of thirty Amaryllidaceae alkaloids have been found, twenty-eight properly identified. Two
contained galanthamine, and seven were able to inhibit AChE.
The timing of the development of specific adaptive immunity after natural SARS-CoV-2 infection, and its relevance in clinical outcome, has not been characterized in depth. Description of the ...long-term maintenance of both cellular and humoral responses elicited by real-world anti-SARS-CoV-2 vaccination is still scarce. Here we aimed to understand the development of optimal protective responses after SARS-CoV-2 infection and vaccination. We performed an early, longitudinal study of S1-, M- and N-specific IFN-γ and IL-2 T cell immunity and anti-S total and neutralizing antibodies in 88 mild, moderate or severe acute COVID-19 patients. Moreover, SARS-CoV-2-specific adaptive immunity was also analysed in 234 COVID-19 recovered subjects, 28 uninfected BNT162b2-vaccinees and 30 uninfected healthy controls. Upon natural infection, cellular and humoral responses were early and coordinated in mild patients, while weak and inconsistent in severe patients. The S1-specific cellular response measured at hospital arrival was an independent predictive factor against severity. In COVID-19 recovered patients, four to seven months post-infection, cellular immunity was maintained but antibodies and neutralization capacity declined. Finally, a robust Th1-driven immune response was developed in uninfected BNT162b2-vaccinees. Three months post-vaccination, the cellular response was comparable, while the humoral response was consistently stronger, to that measured in COVID-19 recovered patients. Thus, measurement of both humoral and cellular responses provides information on prognosis and protection from infection, which may add value for individual and public health recommendations.
B-cell chronic lymphocytic leukemia (B-CLL) is the most common type of leukemia in the Western world. Mutation in different genes, such as
and
, and deletions at specific chromosomic regions, among ...which are 11q or 17p, have been described to be associated to worse disease prognosis. Recent research from our group has demonstrated that, contrary to what is the usual cancer development process through missense mutations, B-CLL is driven by the overexpression of the small GTPase
in its wild-type form without activating mutations. Some mouse models of this disease have been developed to date and are commonly used in B-CLL research, but they present different disadvantages such as the long waiting period until the leukemia fully develops, the need to do cell engraftment or, in some cases, the fact that the model does not recapitulate the alterations found in human patients. We have recently described Rosa26-
xmb1-Cre as a new mouse model of B-CLL with a full penetrance of the disease. In this work, we have validated this mouse model as a novel tool for the development of new therapies for B-CLL, by testing two of the most broadly applied targeted agents: ibrutinib and venetoclax. This also opens the door to new targeted agents against R-RAS2 itself, an approach not yet explored in the clinic.
The Water Framework Directive in Europe requires extending metering and water abstraction controls to accurately satisfy the necessary water resource requirements. However, in situ measurement ...instruments are inappropriate for large irrigation surface areas, considering the high investment and maintenance service costs. In this study, Remote Sensing-based Irrigation Water Accounting (RS-IWA) (previously evaluated for commercial plots, water user associations, and groundwater water management scales) was applied to over 11 Spanish river basin districts during the period of 2014–2018. Using the FAO56 methodology and incorporating remote sensing basal crop coefficient time series to simulate the Remote Sensing-based Soil Water Balance (RS-SWB), we were able to provide spatially and temporally distributed net irrigation requirements. The results were evaluated against the irrigation water demands estimated by the Hydrological Planning Offices and published in the River Basin Management Plans applying the same spatial (Agricultural Demand Units and Exploitation Systems) and temporal (annual and monthly) water management scales used by these public water managers, ultimately returning ranges of agreement (r2 and dr) (Willmott refined index) of 0.79 and 0.99, respectively. Thus, this paper presents an operational tool for providing updated spatio-temporal maps of RS-IWA over large and diverse irrigation surface areas, which is ready to serve as a complementary irrigation water monitoring and management tool.
The purpose of this qualitative instrumental case study was to explore how faculty at a private research university utilize the service-learning pedagogy to advance their scholarship of teaching and ...learning. Of specific interest was what influences them to utilize the service-learning pedagogy in their scholarship of teaching and learning, and how they perceive that utilizing the service-learning pedagogy affects student learning. Boyer’s work on the scholarship of teaching and learning framed the study. The findings of this study are that the experiential components of the service-learning pedagogy are effective in connecting students to real-world problems. As part of the curriculum it engages students in deeper learning and its use changes students’ perspectives about the importance of community involvement, establishing a community consciousness to those students involved. The study supports that the service-learning pedagogy is important to higher education faculty and has led to supporting their scholarship of teaching and learning.
Temporal series maps of irrigated areas, and the
corresponding irrigation water requirements based on remote sensing, is a
recognized tool contributing to water governance at different scales, from
...water user associations to whole river basin districts. These thematic
cartographies offer a first estimation of the crop irrigation requirements,
and a biophysical based approach of the temporal and spatial distribution of
the crop water use in the cultivated areas. This work describes the
operational application of these methodologies, providing valuable
information for water governance and management purposes. The basic products
obtained in the whole Spanish part of the Iberian Peninsula during the
period 2014–2017 were: (i) annual maps of irrigated crops based on time
series of multispectral satellite imagery; and (ii) the direct remote
sensing-based water accounting, by quantifying agricultural water flows
(e.g. rainfall, irrigation, evapotranspiration, drainage and recharge),
through a remote sensing-based soil water balance. Hence this paper provides
a remote sensing based water accounting approach, which relies on dense time
series of multispectral imagery acquired by the multisensor constellation
arranged by Landsat 8 and Sentinel-2 satellites, jointly with meteorological
data and agronomic knowledge. Then, based on these purpose and approach,
annual and monthly maps of net irrigation water requirements have been
elaborated at the most practical spatial and temporal scales for water
governance purposes over big areas such river basin districts. This work
summarizes the methodologies used and discuss the technical and
non-technical feasibility of the proposed approach.
Chronic lymphocytic leukemia (CLL) is a prevalent blood cancer, more common in men in their sixties or older. Unlike some other cancers linked to the KRAS gene, CLL is associated with a gene called ...RRAS2, which is overly active but not mutated. In a significant discovery, we established a mouse model by increasing RRAS2 levels, resulting in CLL development in 100% of cases. This model is essential for testing potential treatments before human trials. In this study, we validated the mouse model by evaluating two widely used CLL drugs, ibrutinib and venetoclax, and found that they effectively killed leukemia cells in the mice. This validation indicates that the mouse model can reliably simulate CLL responses to established drugs. Importantly, it opens the door to testing novel drugs, including those targeting RRAS2, which has not been explored in clinical settings. This advancement is a crucial step toward identifying improved therapies for CLL and holds promise for future developments in leukemia treatment. B-cell chronic lymphocytic leukemia (B-CLL) is the most common type of leukemia in the Western world. Mutation in different genes, such as TP53 and ATM, and deletions at specific chromosomic regions, among which are 11q or 17p, have been described to be associated to worse disease prognosis. Recent research from our group has demonstrated that, contrary to what is the usual cancer development process through missense mutations, B-CLL is driven by the overexpression of the small GTPase RRAS2 in its wild-type form without activating mutations. Some mouse models of this disease have been developed to date and are commonly used in B-CLL research, but they present different disadvantages such as the long waiting period until the leukemia fully develops, the need to do cell engraftment or, in some cases, the fact that the model does not recapitulate the alterations found in human patients. We have recently described Rosa26-RRAS2sup.fl/flxmb1-Cre as a new mouse model of B-CLL with a full penetrance of the disease. In this work, we have validated this mouse model as a novel tool for the development of new therapies for B-CLL, by testing two of the most broadly applied targeted agents: ibrutinib and venetoclax. This also opens the door to new targeted agents against R-RAS2 itself, an approach not yet explored in the clinic.
On TCR ligation, the adaptor Nck is recruited through its src homology 3.1 domain to a proline-rich sequence (PRS) in CD3ε. We have studied the relevance of this interaction for T cell activation in ...vitro and in vivo by targeting the interaction sites in both partners. The first approach consisted of studying a knockin (KI) mouse line (KI-PRS) bearing a conservative mutation in the PRS that makes the TCR incompetent to recruit Nck. This deficiency prevents T cell activation by Ag in vitro and inhibited very early TCR signaling events including the tyrosine phosphorylation of CD3ζ. Most important, KI-PRS mice are partly protected against the development of neurological symptoms in an experimental autoimmune encephalitis model, and show a deficient antitumoral response after vaccination. The second approach consisted of using a high-affinity peptide that specifically binds the src homology 3.1 domain and prevents the interaction of Nck with CD3ε. This peptide inhibits T cell proliferation in vitro and in vivo. These data suggest that Nck recruitment to the TCR is fundamental to mount an efficient T cell response in vivo, and that the Nck-CD3ε interaction may represent a target for pharmacological modulation of the immune response.
Modulating T cell activation is critical for treating autoimmune diseases but requires avoiding concomitant opportunistic infections. Antigen binding to the T cell receptor (TCR) triggers the ...recruitment of the cytosolic adaptor protein Nck to a proline-rich sequence in the cytoplasmic tail of the TCR's CD3ε subunit. Through virtual screening and using combinatorial chemistry, we have generated an orally available, low-molecular weight inhibitor of the TCR-Nck interaction that selectively inhibits TCR-triggered T cell activation with an IC
(median inhibitory concentration) ~1 nM. By modulating TCR signaling, the inhibitor prevented the development of psoriasis and asthma and, furthermore, exerted a long-lasting therapeutic effect in a model of autoimmune encephalomyelitis. However, it did not prevent the generation of a protective memory response against a mouse pathogen, suggesting that the compound might not exert its effects through immunosuppression. These results suggest that inhibiting an immediate TCR signal has promise for treating a broad spectrum of human T cell-mediated autoimmune and inflammatory diseases.
The adaptor protein Nck is inducibly recruited through its SH3.1 domain to a proline-rich sequence (PRS) in CD3ε after TCR engagement. However, experiments with a knockin mutant bearing an 8-aa ...replacement of the PRS have indicated that Nck binding to the TCR is constitutive, and that it promotes the degradation of the TCR in preselection double-positive (DP) CD4(+)CD8(+) thymocytes. To clarify these discrepancies, we have generated a new knockin mouse line (KI-PRS) bearing a conservative mutation in the PRS resulting from the replacement of the two central prolines. Thymocytes of KI-PRS mice are partly arrested at each step at which pre-TCR or TCR signaling is required. The mutation prevents the trigger-dependent inducible recruitment of endogenous Nck to the TCR but does not impair TCR degradation. However, KI-PRS preselection DP thymocytes show impaired tyrosine phosphorylation of CD3ζ, as well as impaired recruitment of ZAP70 to the TCR and impaired ZAP70 activation. Our results indicate that Nck is recruited to the TCR in an inducible manner in DP thymocytes, and that this recruitment is required for the activation of early TCR-dependent events. Differences in the extent of PRS mutation could explain the phenotypic differences in both knockin mice.
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